We all know what happens when the fox guards the chicken coop -- or do we?

This is not a rhetorical question. Do we Americans understand what happens when a wily predator is custodian of defenseless clucks? Our state of psychological disarmament makes us unable to recognize even such an obvious threat. I can’t think of another explanation for why the country hasn’t melted down the Capitol switchboard with phone calls to U.S. senators beseeching them not to confirm John Brennan as the next director of the CIA.

What’s so scary about Brennan, currently President Obama’s top adviser for counterterrorism?

More than any other Obama administration official, Brennan has openly cultivated groups in this country that I describe, with good reason, as being of the jihadist persuasion. Simultaneously, Brennan misinforms or dissembles about the nature of jihad itself. How can such a man helm America’s premier intelligence institution, which, at least ostensibly, is engaged in thwarting jihad?

Consider Brennan’s interactions with the Islamic Society of North America (ISNA). Despite evidence presented (and later upheld) in federal court during the landmark 2008 Holy Land Foundation trial, which established ISNA as a Muslim Brotherhood organization and financial supporter of the terrorist organization Hamas (a wing of the Muslim Brotherhood), Brennan has continued to meet with ISNA officials and participate in ISNA events.

At ISNA’s annual conference in 2009, for example, Brennan delivered the keynote address. In 2010, Brennan spoke at a “town hall” with ISNA president Ingrid Mattson. As former FBI agent John Guandolo wrote recently in a paper he shared with me, Brennan continues to grant ISNA leaders access to senior government officials and support their appointments to key intelligence positions. (Guandolo and I are among the 19 co-authors of “Shariah: The Threat to America.”)

“The current president of ISNA, Imam Mohamed Magid, sits on the Homeland Security Advisory Council, which reports directly to (Homeland) Secretary (Janet) Napolitano,” Guandolo writes. “With the support of John Brennan, Imam Magid works with the National Security Council, which has publicly applauded this Hamas supporter.”

Guandolo was referring to praise heaped on Magid in 2011 by then-deputy national security adviser Denis McDonough. McDonough is now Obama’s chief of staff.

If this all sounds surreal, welcome to our world. Here, the leader of a group that the U.S. government has designated a conspirator to promote and finance Islamic terrorism is tapped to advise the same government on how to defuse Islamic terrorism -- or, rather, what the government prefers to call “extremism.”

The flip side to this affinity for Muslim Brotherhood groups is hostility toward officials who dare to unmask them. Last year, a reporter asked Brennan to assess extremely alarming evidence of Muslim Brotherhood penetration of the U.S. government brought forward by five House Republicans led by Rep. Michele Bachmann -- “the National Security Five,” as Newt Gingrich would dub them. Brennan’s reaction was to dismiss the charges and the elected representatives. “I have no idea what it is that they are making reference to,” Brennan said, “and I’m not even going to try to divine what it is that sometimes comes out of Congress.”

His reaction is much the same when it comes to what is called, in military parlance, the “enemy threat doctrine.” Take jihad. We must not “describe our enemy as ‘jihadists’ or ‘Islamists,’” Brennan said in 2010, “because jihad is a holy struggle, a legitimate tenet of Islam, meaning to purify oneself or one’s community.”

This notion of “jihad” as self-help is often disseminated by dupes in ignorance. It is deception, or “taqiyya,” however, when voiced by those who know better. Nonviolent jihad barely shows up in the Quran. (Sorbonne Ph.D. linguist Tina Magaard came up with only one appearance of spiritual struggle in her detailed textual analysis of the Quran -- as opposed to 50 references that invoke violent aggression.) Meanwhile, the first definition of “jihad” in the authoritative Sunni law book “Reliance of the Traveller” reads: “Jihad means to war against non-Muslims.”

If intelligence expert Brennan knows this, he doesn’t like to talk about it. When he was pressed in 2010 by a member of the Washington Times editorial page for an example of armed jihad in history, Brennan packed up his papers and abruptly left the meeting. I recently watched a video of the meeting, which is on YouTube, and his behavior is very strange.

So are his ideas about Islam and jihad. “Al-Qaida has perverted Islam and has corrupted the concept of Islam,” Brennan declared in a 2010 press conference, thereby obscuring the clear Quranic imperatives on waging jihad that drove Umar Farouk Abdulmutallab, the so-called underwear bomber, to try to bring down a passenger plane over Detroit on Christmas Day 2009. Why does Brennan, a counterterrorism expert, say such things?

Guandolo offers two possible reasons: 1) Brennan is “functionally incapable of reasonable ... thought on this matter,” or 2) he is “intentionally misleading U.S. government leaders on al-Qaida’s stated objectives and how they marry up to the requirements of Shariah (Islamic law).”

Either reason disqualifies John Brennan to be CIA director. Still, not one single senator has raised this crucial matter during confirmation hearings.

There is something else. Guandolo has gone public with an allegation that Brennan, while CIA station chief in Saudi Arabia in the 1990s, converted to Islam. This allegation is based on anonymous sources within the government who, Guandolo says, “have direct knowledge” of the conversion.

Given Guandolo’s own counterterrorism expertise as an FBI subject-expert in Islam and professional observer of the Muslim Brotherhood, his charges carry heft. Detractors try to undermine them by resurrecting an inappropriate sexual relationship Guandolo had as an FBI agent with an FBI informant during a high-profile corruption investigation. This might be relevant if, for example, Guandolo were running for office as a traditional values candidate. He is, however, trying to get information he discovered using his skills as an investigator into the public square for evaluation.

He’s halfway there -- that is, the story has entered the pubic square via talk radio, the blogosphere and the news media, including WND.com, MSNBC, TheBlaze, The Atlantic, U.S. News & World Report, the Daily Mail and Al Arabiya. Will it be evaluated? It should, for what Guandolo believes it tells us about Brennan.

“Why has (Brennan) kept this piece of information secret?” Guandolo writes. “The reason appears to be self-evident ... Mr. Brennan’s conversion to Islam was the culmination of a hostile campaign by a foreign intelligence service ... Someone who has been recruited by a foreign government has necessarily demonstrated he is susceptible to easy manipulation by others and should certainly not lead one of America’s intelligence agencies.”

Case closed, I’d say. But what about the chicken coop?

Diana West is the author of “The Death of the Grown-up: How America’s Arrested Development Is Bringing Down Western Civilization,” and blogs at dianawest.net. She can be contacted via dianawest@verizon.net. Follow her on Twitter @diana_west